How many slaves could opt in? How many were given free education, free food, free room and board? How many were allowed to request a transfer? or to simply quit at any moment and do anything else with their time? How many were offered bags of money in the south to go and be a slave for someone else?
The short-sightedness of this feel-good position is that it unjustly lightens the horrid conditions actual slaves went through. I suppose some people see partially overlapping ideas and take that to mean equivalence without discriminating. Slaves actually existed, they were actually owned, bought, sold, beaten, killed. That was a real part of world and American history. They weren't waiting 3-5 years to either play professional slavery or join the workforce. They weren't minor celebrities on their plantation.
The sensational statement no longer grabs people like it used to; likely because language has been weaponized and subsequently neutered. You are reducing the weight of slavery and I think that's a terrible misstep.
Student-athletes were not paid what an open-market would support. They weren't paid what we now feel they 'deserved' or 'earned' due to a special skillset.